We present optical, near-infrared (NIR) images and spectra of the
compact, dusty
and complex HII region N88A in the SMC. The data were obtained mainly in the
visible with the Boller &
Chivens (B&C) spectrograph at the ESO 1.5 m telescope and recently with the
infrared
spectrometer and array camera (ISAAC) at the VLT, around 2 μm.
The NIR observations identified a region emitting in H2, both
in and around the two major components of N88. Using long-slit spectra
obtained in the 3600–10 100 Å wavelength range we have re-determined the key physical
parameters of electron temperature and densities. The spectral type of the
complex exciting source of N88A has been classified as an O6-O8 V, using He and H lines in the visible and NIR, with
the HeI 1.7 μm/2.11 μm line ratio in the K band spectrum, suggesting that
N88A is effectively ionized by a source of type <O7 V. However, from reddening correction and the temperature
determined by photoionization model calculations, the ionizing source should also contain a very early type
O star.
A comparison with a recent photometric
study shows that the V magnitude of the exciting source of N88A has previously been
overestimated. The chemical abundances of He, O, N, Ne, S, and Ar, from emission-line intensities,
are also derived. Abundancies are consistent with the average abundances for SMC HII regions.

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